XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3141
and NaHA hindered the adsorption of collector DDTC on
pyrite surface, so the combined depressants had a strong
depression effect on pyrite.
Wettability Analysis
The contact angles of galena and pyrite in the presence of
different reagents were illustrated in Figure 7 and Figure 8.
In the absence of reagents, the contact angles of galena and
pyrite were 65.47° and 20.43°, respectively, indicating that
galena had good natural floatability while pyrite had poor
natural floatability. After adding the collector DDTC, the
contact angles of galena and pyrite were 72.55° and 48.17°,
respectively, indicating that collector DDTC adsorbed on
the surface of galena and pyrite. In the presence of depres-
sants Ca2+and NaHA, the contact angles of galena and
pyrite were 40.27° and 19.54°, indicating that combined
depressants adsorbed on the surface of galena and pyrite.
When combination depressants and collector were present,
the contact angle of galena was 59.91°, indicating that col-
lector DDTC adsorbed on the surface of galena in the pres-
ence of combined depressants while the contact angle of
pyrite was 24.98°, indicating that the combination depres-
sants hindered the adsorption of the collector on the pyrite
surface. The results were in agreement with the flotation
results.
Raman Spectroscopy Tests
Raman spectroscopy can provide many important informa-
tion about materials, such as the structure and composition
of molecules, molecular interactions and the structure of
surfaces. Figure 9 illustrated the Raman spectrum of NaHA.
As illustrated in Figure 9, Raman peak of NaHA was found
at 1362.09cm–1 and 1594.65cm–1. The Raman peak at
1362.09cm–1 was generated by the symmetric vibration
of carboxyl group, and the Raman peak at 1594.65cm–1
was generated by the vibration of the C=C bond structure
of aromatic carboxyl group in NaHA, the vibration of the
C-O bond of phenolic group and the phenolic vibration of
NaHA[33].
Raman spectrum of pyrite and galena with and with-
out depressant was shown in Figure 10. In the absence of
depressant, Raman peaks of pyrite appeared at 342.40cm–1
and 382.21cm–1, which were caused by the stretching vibra-
tion of pyrite Fe-[S2]. After interaction with depressant,
the Raman spectrum of galena changed little, while the
Raman peak of NaHA appeared obviously in the Raman
spectrum of pyrite, indicating that the depressant chemical
65.47°
a
72.55°
b
40.27°
c
59.91°
d
Figure 7. Contact angles of galena (a), galena +DDTC (b), galena +Ca2++NaHA (c) and galena +Ca2++ NaHA+ DDTC (d)
20.43° a 48.17° b 19.54°
c
24.98° d
Figure 8. Contact angles of pyrite (a), pyrite +DDTC (b), pyrite +Ca2++NaHA (c) and pyrite +Ca2++ NaHA+ DDTC (d)
0 500 1000 1500 2000 2500 3000
NaHA
Raman shift (cm -1 )
1594.65
1362.09
Figure 9. Raman spectrum of NaHA
and NaHA hindered the adsorption of collector DDTC on
pyrite surface, so the combined depressants had a strong
depression effect on pyrite.
Wettability Analysis
The contact angles of galena and pyrite in the presence of
different reagents were illustrated in Figure 7 and Figure 8.
In the absence of reagents, the contact angles of galena and
pyrite were 65.47° and 20.43°, respectively, indicating that
galena had good natural floatability while pyrite had poor
natural floatability. After adding the collector DDTC, the
contact angles of galena and pyrite were 72.55° and 48.17°,
respectively, indicating that collector DDTC adsorbed on
the surface of galena and pyrite. In the presence of depres-
sants Ca2+and NaHA, the contact angles of galena and
pyrite were 40.27° and 19.54°, indicating that combined
depressants adsorbed on the surface of galena and pyrite.
When combination depressants and collector were present,
the contact angle of galena was 59.91°, indicating that col-
lector DDTC adsorbed on the surface of galena in the pres-
ence of combined depressants while the contact angle of
pyrite was 24.98°, indicating that the combination depres-
sants hindered the adsorption of the collector on the pyrite
surface. The results were in agreement with the flotation
results.
Raman Spectroscopy Tests
Raman spectroscopy can provide many important informa-
tion about materials, such as the structure and composition
of molecules, molecular interactions and the structure of
surfaces. Figure 9 illustrated the Raman spectrum of NaHA.
As illustrated in Figure 9, Raman peak of NaHA was found
at 1362.09cm–1 and 1594.65cm–1. The Raman peak at
1362.09cm–1 was generated by the symmetric vibration
of carboxyl group, and the Raman peak at 1594.65cm–1
was generated by the vibration of the C=C bond structure
of aromatic carboxyl group in NaHA, the vibration of the
C-O bond of phenolic group and the phenolic vibration of
NaHA[33].
Raman spectrum of pyrite and galena with and with-
out depressant was shown in Figure 10. In the absence of
depressant, Raman peaks of pyrite appeared at 342.40cm–1
and 382.21cm–1, which were caused by the stretching vibra-
tion of pyrite Fe-[S2]. After interaction with depressant,
the Raman spectrum of galena changed little, while the
Raman peak of NaHA appeared obviously in the Raman
spectrum of pyrite, indicating that the depressant chemical
65.47°
a
72.55°
b
40.27°
c
59.91°
d
Figure 7. Contact angles of galena (a), galena +DDTC (b), galena +Ca2++NaHA (c) and galena +Ca2++ NaHA+ DDTC (d)
20.43° a 48.17° b 19.54°
c
24.98° d
Figure 8. Contact angles of pyrite (a), pyrite +DDTC (b), pyrite +Ca2++NaHA (c) and pyrite +Ca2++ NaHA+ DDTC (d)
0 500 1000 1500 2000 2500 3000
NaHA
Raman shift (cm -1 )
1594.65
1362.09
Figure 9. Raman spectrum of NaHA